The present invention relates to a damper drive system in a combined microwave and electric heater oven for controlling the direction of the forced air flow created by a fan system.
In a combined microwave and electric heater oven, a fan system is provided for cooling a magnetron disposed in a space formed between an oven wall and a housing of the combined microwave and electric heater oven. The forced air flow created by the fan system is introduced into the oven cavity for discharging the gas generated in the oven cavity during the microwave cooking operation. The air flow must not be introduced into the oven cavity during the electric heater cooking operation, because the interior of the oven cavity must be maintained at a high temperature during the electric heater cooking operation. However, even during the electric heater cooking operation, the fan system is continuously operated in order to protect the magnetron from the high temperature generated by the electric heater.
Therefore, a damper mechanism is normally provided in the combined microwave and electric heater oven for selectively introducing the forced air flow into the oven cavity. A typical construction of the combined microwave and electric heater oven including a damper mechansim is described in copending application Ser. No. 138,749, "DAMPER ACTIVATION IN A COMBINED MICROWAVE AND ELECTRIC HEATING OVEN", filed on Apr. 9, 1980 by Yasuo Shin now U.S. Pat. No. 4,369,347, patented Jan. 18, 1983 and assigned to the same assignee as the present invention.
Accordingly, an object of the present invention is to provide a novel damper drive system in a combined microwave and electric heater oven.
Another object of the present invention is to simplify a damper drive mechanism in a combined microwave and electric heater oven.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
To achieve the above objects, pursuant to an embodiment of the present invention, a motor is provided to open or close the damper. A relay switch mechanism is provided for energizing the motor at a desired time. A detection system is associated with the damper, which develops a detection signal when the damper is completely opened or when the damper is completely closed. In response to the thus developed detection signal, the relay switch mechanism is turned off, thereby deenergizing the motor.